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941.
942.
BASHAR ALDHOON M.D. Ph.D. DAVID S. FRANKEL M.D. MATHEW D. HUTCHINSON M.D. DAVID J. CALLANS M.D. ANDREW E. EPSTEIN M.D. SANJAY DIXIT M.D. MICHAEL P. RILEY M.D. Ph.D. DAVID LIN M.D. FERMIN C. GARCIA M.D. GREGORY E. SUPPLE M.D. JOSHUA M. COOPER M.D. RUPA BALA M.D. RAJAT DEO M.D. ERICA S. ZADO P.A.‐C. FRANCIS E. MARCHLINSKI M.D. 《Journal of cardiovascular electrophysiology》2014,25(3):293-298
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Mike Lin Shoa-Lin Lin Kuei-Liang Wang Hsien-Wen Kuo Tahir Tak 《The International journal of angiology》2014,23(4):233-242
Aging is associated with degenerative changes in cardiac and endothelial function (EF). This study was done to assess whether age-related changes take place on EF, carotid intima-media thickness (IMT), blood pressure (BP), and echocardiographic measurements. All volunteers were healthy normotensive healthy subjects. They were divided into three groups. Group 1, young adults: < 40 years old; Group 2, middle age: between 40 and 60 years old; Group 3, elderly: > 60 years old. High-frequency vascular ultrasound was used to assess the baseline brachial artery dimension and flow velocity after reactive hyperemia. The carotid IMT and echocardiographic measurements including Doppler variables were recorded in all subjects. Systolic BP, left ventricular mass, and left ventricular end-diastolic volume increased progressively with age (p < 0.001). Left ventricular ejection fraction decreased progressively with age (male, p = 0.034; female, p = 0.001); E/A ratio of the left ventricular flow spectrum declined with age (p < 0.001). The ultrasonic EF variables of flow increased during reactive hyperemia and IMT increased with age (p < 0.001). Our study demonstrates that BP, body weight, and ultrasonic variables changed significantly with age. The aging-associated changes provide insight into progression to atherosclerosis. 相似文献
946.
《Journal of cardiac failure》2014,20(8):548-554
BackgroundReduced exercise tolerance from impaired cardiac output is an important criterion for left ventricular assist device (LVAD) implantation. However, little is known about how exercise capacity changes after LVAD and how changes compare with patients undergoing heart transplantation.Methods and ResultsWe compared changes in cardiopulmonary exercise testing performed pre- and postoperatively in patients who underwent HeartMate II LVAD implantation (n = 25) and heart transplantation (n = 74) at the Mayo Clinic in Rochester, Minnesota, between 2007 and 2012. Preoperatively, patients undergoing LVAD and transplant had markedly reduced exercise time (mean 5.1 minutes [45% predicted] and 5.0 minutes [44% predicted], respectively), low peak oxygen consumption (VO2; mean 11.5 mL·kg·min [43% predicted] and 11.9 mL·kg·min [38% predicted]), and abnormal ventilatory gas exchange (ratio of minute ventilation to carbon dioxide production [VE/VCO2] nadir 39.4 and 37.4). After LVAD and transplant, there were similar improvements in exercise time (mean Δ +1.2 vs. 1.7 minutes, respectively, P = .27) and VE/VCO2 nadir (mean Δ −3.7 vs. −4.2, P = .74). However, peak VO2 increased posttransplant but did not change post-LVAD (mean Δ +5.4 vs. +0.9 mL·kg·min, respectively, P < .001). Most patients (72%) had a peak VO2 < 14 mL·kg·min post-LVAD.ConclusionsAlthough improvements in exercise capacity and gas exchange are seen after LVAD and heart transplant, peak VO2 doesn't improve post-LVAD and remains markedly abnormal in most patients. 相似文献
947.
Estrogens regulate key features of metabolism, including food intake, body weight, energy expenditure, insulin sensitivity, leptin sensitivity, and body fat distribution. There are two ‘classical’ estrogen receptors (ERs): estrogen receptor alpha (ERS1) and estrogen receptor beta (ERS2). Human and murine data indicate ERS1 contributes to metabolic regulation more so than ESR2. For example, there are human inactivating mutations of ERS1 which recapitulate aspects of the metabolic syndrome in both men and women. Much of our understanding of the metabolic roles of ERS1 was initially uncovered in estrogen receptor α-null mice (ERS1−/−); these mice display aspects of the metabolic syndrome, including increased body weight, increased visceral fat deposition and dysregulated glucose intolerance. Recent data further implicate ERS1 in specific tissues and neuronal populations as being critical for regulating food intake, energy expenditure, body fat distribution and adipose tissue function. This review will focus predominantly on the role of hypothalamic ERs and their critical role in regulating all aspects of energy homeostasis and metabolism. 相似文献
948.
Introduction
The natural history of acute pulmonary embolism (PE) under treatment is about a gradual resolution of the thrombi, and uncommonly, the development of chronic thromboembolic pulmonary hypertension (CTEPH). We hypothesized that ventilatory efficiency parameters during cardiopulmonary exercise testing (CPET) may be able to monitor the process and predict CTEPH.Methods
15 patients rehabilitated from acute PE (total resolution of thrombi), 44 patients with chronic PE (with residual thrombi), 66 patients with CTEPH, and 36 sedentary healthy controls performed incremental CPET.Results
The lowest VE/VCO2 was higher in CTEPH patients than that in chronic PE and rehabilitated patients (43.4 L/min vs 29.9 L/min vs 27.1 L/min, p < 0.005). The VE/VCO2 slope (48.4 L/min/L/min vs 29.9 L/min/L/min vs 28.0 L/min/L/min, p < 0.005) and oxygen uptake efficiency plateau (OUEP) (37.1 L/min vs 27.0 L/min vs 25.2 L/min, p < 0.005) had the similar changes. In logistic regression analysis, the lowest VE/VCO2 ≥ 34.35 L/min was the best predictor of CTEPH (OR 159.0, 95% CI 36.0-702.3, p < 0.001). The lowest VE/VCO2 was higher in chronic PE patients compared with the controls (29.9 L/min vs 26.5 L/min, p < 0.05), but there was no difference between the rehabilitated patients and the controls. In multiple linear regression analysis, the percentage of vascular obstruction by ventilation-perfusion lung scanning (PVO) was the most significant independent predictor for indices of ventilatory efficiency in chronic PE and rehabilitated patients.Conclusions
CTEPH is associated with weakened ventilatory efficiency. The lowest VE/VCO2 ratio has the best capability to predict CTEPH. Ventilatory inefficiency improves along with recovery of acute PE. 相似文献949.
Franco Casazza Amedeo Bongarzoni Chiara Forgione Claudio Cuccia Ferdinando Imperadore Girolamo Arrigo Irene Floriani Luigi Pignataro 《Thrombosis research》2014
Aims
The aim of the study is to describe the course of the echocardiographically measured pulmonary artery systolic pressure (PAsP) in a series of patients included in the Italian Pulmonary Embolism Registry (IPER).Methods
Patients with confirmed PE received an echo-Doppler evaluation within 24 hours from hospital admission and after one year. Pulmonary hypertension (PH) was considered “likely” , “possible” or “unlikely” with a right ventricular-right atrial (RV-RA) pressure gradient > 45 mm Hg, between 32 and 45 mm Hg and ≤ 31 mm Hg and no additional echocardiographic variables suggestive of PH, respectively.Results
We studied 286 patients (169 females and 117 males, mean age 67 ± 15; mean follow-up 387 ± 45 days): 240 had a baseline tricuspid regurgitation (TR) and a RV-RA gradient of variable degree. PH was considered likely, unlikely and possible in 97, 93 and 50 patients respectively. At FU echocardiography, 6 patients (2.1%) had a likely PH and all of them were part of the group of 97 patients with a baseline likely PH; 24 patients (8.4%) had a possible PH, and 67% of them had an initial likely PH. No patients with a baseline unlikely PH or without TR developed a follow-up PH (both likely or possible). The probability to show a likely PH at FU echocardiography for patients with a baseline RV-RA gradient > 45 mm Hg was 6.2%, while the probability not to have a likely PH for patients with a baseline RV-RA gradient ≤ 45 mm Hg was 100%.Conclusion
In our study population of patients with acute PE, we observed that those presenting with a baseline echocardiographic RV-RA pressure gradient ≤ 45 mm Hg were completely free from a likely PH after 1-year. 相似文献950.
Tetralogy of Fallot with restrictive ventricular septal defect by accessory tricuspid leaflet tissue
In tetralogy of Fallot septal defect is usually large because of malalignment of outlet septum, restrictive defect has been reported rarely. We present a case of tetralogy of Fallot with accessory tricuspid leaflet tissue restricting ventricular septal defect. The report includes echocardiographic and catheter images of this rare presentation of tetralogy of Fallot. 相似文献